Abstract
Consumption or handling of poultry and poultry products contaminated with Campylobacter species are a leading cause of foodborne illness in humans. Current strategies employed to reduce Campylobacter in live chickens provide inconsistent results indicating the need for an alternative approach. This study investigated the efficacy of phytochemicals, namely, turmeric, curcumin, allyl sulfide, garlic oil, and ginger oil, to reduce Campylobacter jejuni in postharvest poultry and sought to delineate the underlying mechanisms of action. Two experiments were conducted on the thigh skin of the chicken, and each experiment was repeated twice. Samples were inoculated with 50 μl (∼107 CFU/sample) of C. jejuni strain S-8 and allowed to adhere for 30 min. Skin samples were dipped into their respective prechilled treatment solutions (0.25 and 0.5% in experiments 1 and 2, respectively) at 4°C for an hour to simulate chilling tank treatment, followed by plating to enumerate C. jejuni (n = 3 samples/treatment/trial). The mechanisms of action(s) were investigated using subinhibitory concentration (SIC) in adhesion, quorum sensing, and gene expression analyses. Adhesion assay was conducted on the monolayers of ATCC CRL-1590 chicken embryo cells challenged with C. jejuni and incubated in the presence or absence of phytochemicals for 1.5 h, followed by plating to enumerate adhered C. jejuni. The effects of phytochemicals on quorum sensing and cell viability were investigated using Vibrio harveyi bioluminescence and LIVE/Dead BacLightTM bacterial viability assays, respectively. In addition, droplet digital PCR determined the gene expression analyses of C. jejuni exposed to phytochemicals. Data were analyzed by GraphPad Prism version 9. C. jejuni counts were reduced by 1.0–1.5 Log CFU/sample with garlic oil or ginger oil at 0.25 and 0.5% (p < 0.05). The selected phytochemicals (except curcumin) reduced the adhesion of C. jejuni to chicken embryo cells (p < 0.05). In addition, all the phytochemicals at SIC reduced quorum sensing of C. jejuni (p < 0.05). The cell viability test revealed that cells treated with 0.25% of phytochemicals had compromised cell membranes indicating this as a mechanism that phytochemicals use to damage/kill C. jejuni. This study supports that the application of phytochemicals in postharvest poultry would significantly reduce C. jejuni in poultry meat.
Highlights
Campylobacter jejuni and Campylobacter coli are foodborne pathogens that cause gastroenteritis in humans and affect around 95 million people annually worldwide (Scallan et al, 2011; Kirk et al, 2015)
The garlic oil and ginger oil were as effective as peracetic acid (PAA) in reducing C. jejuni
In contrast to garlic oil and ginger oil, turmeric, curcumin, and allyl sulfide at 0.25% dose failed to reduce C. jejuni counts compared with the controls
Summary
Campylobacter jejuni and Campylobacter coli are foodborne pathogens that cause gastroenteritis (campylobacteriosis) in humans and affect around 95 million people annually worldwide (Scallan et al, 2011; Kirk et al, 2015). In the United States alone, more than 1.3 million human campylobacteriosis cases are reported every year and leads to an economic burden of $1.9 billion (Scallan et al, 2011; Batz et al, 2014; Marder et al, 2017). It is reported that ∼58% of C. jejuni outbreaks in 2018 were implicated to poultry and poultry products [IFSAC (Interagency Food Safety Analytics Collaboration), 2020]. This pathogen primarily resides in the gastrointestinal tract of poultry and caused contamination of meat during poultry processing. Handling of uncooked meat and consumption of undercooked meat are the primary sources of human Campylobacter infections [Acheson and Allos, 2001; Altekruse and Tollefson, 2003; Taylor et al, 2013; IFSAC (Interagency Food Safety Analytics Collaboration), 2020]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
